Clean Os(0001) electronic surface states: a first-principle fully relativistic investigation

TL;DR

This study uses fully relativistic density functional theory to analyze the electronic surface states of Os(0001), revealing Rashba split resonances and their spin polarization, with comparisons to other noble metal surfaces.

Contribution

First-principles relativistic calculations of Os(0001) surface states, including spin-orbit effects and spin polarization analysis, providing new insights into surface electronic structures.

Findings

No surface state in the gap similar to L-gap of (111) surfaces

Presence of Rashba split resonances crossing the Fermi level

Variable spin polarization behavior depending on state interactions

Abstract

We analyze the electronic structure of the Os(0001) surface by means of first-principle calculations based on Fully Relativistic (FR) Density Functional Theory (DFT) and a Projector Augmented-Wave (PAW) approach. We investigate surface states and resonances analyzing their spin-orbit induced energy splitting and their spin polarization. The results are compared with previously studied surfaces Ir(111), Pt(111), and Au(111). We do not find any surface state in the gap similar to the L-gap of the (111) fcc surfaces, but find Rashba split resonances that cross the Fermi level and, as in the recently studied Ir(111) surface, have a characteristic downward dispersion. Moreover, for some selected surface states we study the spin polarization with respect to ${\bf k}_{\parallel}$, the wave-vector parallel to the surface. In some cases, such as the Rashba split resonances, the spin polarization shows a smooth behavior with slow rotations, in others the rotation is faster, due to mixing and anti-crossing of the states.